Augmented and Virtual Reality for Use with Neuromodulation Therapy

ABSTRACT

A virtual or augmented reality system is disclosed which is capable of both (i) evaluating prospective implantable neurostimulator patient candidates, and (ii) determining optimal stimulation settings for already-implanted neurostimulation patients. Physiological sensors are included with the system to provide objective measurements relevant to a patient&#39;s symptoms, such as pain in a Spinal Cord Stimulation (SCS) system. Such objective measurements are determined during the presentation of various virtual or augmented environments, and can be useful to determining which patients are suitable candidates to consider for implantation. Stimulation settings for already-implanted patients may be adjusted while presenting a virtual or augmented environment to the patient, with objective measurements being determined for each stimulation setting. Such objective measurements can then be used to determine optimal stimulation settings for the patient.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a non-provisional application of U.S. Provisional PatentApplication Ser. No. 62/711,734, filed Jul. 30, 2018, to which priorityis claimed, and which is incorporated by reference in its entirety.

FIELD OF THE TECHNOLOGY

The present application is related to techniques to improve patientselectivity and the effectiveness of therapy provided byneurostimulation devices.

INTRODUCTION

Implantable stimulation devices are devices that generate and deliverelectrical stimuli to nerves and tissues for the therapy of variousbiological disorders, such as pacemakers to treat cardiac arrhythmia,defibrillators to treat cardiac fibrillation, cochlear stimulators totreat deafness, retinal stimulators to treat blindness, musclestimulators to produce coordinated limb movement, spinal cordstimulators to treat chronic pain, cortical and deep brain stimulatorsto treat motor and psychological disorders, and other neural stimulatorsto treat urinary incontinence, sleep apnea, shoulder subluxation, etc.The description that follows will generally focus on the use of thetechniques within a Spinal Cord Stimulation (SCS) system, such as thatdisclosed in U.S. Pat. No. 6,516,227. However, the described techniquesmay find applicability in any implantable medical device system,including a Deep Brain Stimulation (DBS) system.

As shown in FIG. 1, a traditional SCS system includes an implantableneurostimulator such as an Implantable Pulse Generator (IPG) 10 (orimplantable medical device, more generally), which includes abiocompatible device case 12 formed of titanium, for example. The case12 typically holds the circuitry and battery 14 (FIG. 2) necessary forthe IPG 10 to function, which battery 14 may be either rechargeable orprimary in nature. The IPG 10 delivers electrical stimulation to apatient's nerves and tissues through electrodes 16, which, in a SCSsystem are typically implantable within the epidural space within apatient's spinal column. Common electrode arrangements include a lineararrangement along a percutaneous lead 18 and a two-dimensionalarrangement on a paddle lead 60. The proximal ends of the leads 18 and60 include lead connectors 20 that are connectable to the IPG 10 at oneor more connector blocks 22 fixed in a header 24, which can comprise anepoxy, for example. Contacts in the connector blocks 22 make contactwith electrode terminals in the lead connectors 20, and communicate withthe circuitry inside the case 12 via feedthrough pins 26 passing througha hermetic feedthrough 28 to allow such circuitry to provide stimulationto or monitor the various electrodes 16. The number and arrangement ofelectrodes on a percutaneous lead 18 or a paddle lead 60 can vary. Whenpercutaneous leads 18 are employed, it is common for two such leads 18to be implanted with one each on the right and left side of the spinalcord.

As shown in FIG. 2, IPG 10 contains a charging coil 30 for wirelesscharging of the IPG's battery 14 using an external charger 50, assumingthat battery 14 is a rechargeable battery. If IPG 10 has anon-rechargeable (primary) battery 14, charging coil 30 in the IPG 10and the external charger 50 can be eliminated. IPG 10 also contains atelemetry coil antenna 32 for wirelessly communicating data with anexternal controller device 40, which is explained further below. Inother examples, antenna 32 can comprise a short-range RF antenna such asa slot, patch, or wire antenna. IPG 10 also contains control circuitrysuch as a microcontroller 34, and one or more Application SpecificIntegrated Circuit (ASICs) 36, which can be as described for example inU.S. Pat. No. 8,768,453. ASIC(s) 36 can include stimulation circuitryfor providing stimulation pulses at one or more of the electrodes 16 andmay also include telemetry modulation and demodulation circuitry forenabling bidirectional wireless communications at antenna 32, batterycharging and protection circuitry coupleable to charging coil 30,DC-blocking capacitors in each of the current paths proceeding to theelectrodes 16, etc. Components within the case 12 are integrated via aprinted circuit board (PCB) 38.

FIG. 2 further shows the external devices referenced above, which may beused to communicate with the IPG 10, in plan and cross section views.External controller (or, remote controller) 40 may be used to controland monitor the IPG 10 via a bidirectional wireless communication link42 passing through a patient's tissue 5. For example, the externalcontroller 40 may be used to provide or adjust a stimulation program forthe IPG 10 to execute that provides stimulation to the patient. Thestimulation program may specify an electrode configuration that includesa number of stimulation parameters, such as which electrodes areselected for stimulation; whether such active electrodes are to act asanodes or cathodes; and the amplitude (e.g., current), frequency, andduration of stimulation at the active electrodes, assuming suchstimulation comprises stimulation pulses as is typical.

Communication on link 42 can occur via magnetic inductive couplingbetween a coil antenna 44 in the external controller 40 and the IPG 10'stelemetry coil 32 as is well known. Typically, the magnetic fieldcomprising link 42 is modulated, for example via Frequency Shift Keying(FSK) or the like, to encode transmitted data. For example, datatelemetry via FSK can occur around a center frequency of fc=125 kHz,with a 129 kHz signal representing transmission of a logic ‘1’ bit and a121 kHz signal representing a logic ‘0’ bit. However, transcutaneouscommunications on link 42 need not be by magnetic induction, and maycomprise short-range RF telemetry (e.g., Bluetooth, WiFi, Zigbee, MICS,etc.) if antennas 44 and 32 and their associated communication circuitryare so configured. The external controller 40 is generally similar to acell phone and includes a hand-holdable, portable housing.

External charger 50 provides power to recharge the IPG's battery 14should that battery be rechargeable. Such power transfer occurs byenergizing a charging coil 54 in the external charger 50, which producesa magnetic field comprising transcutaneous link 52, which may occur witha different frequency (f₂=80 kHz) than data communications on link 42.This magnetic field 52 energizes the charging coil 30 in the IPG 10,which is rectified, filtered, and used to recharge the battery 14. Link52, like link 42, can be bidirectional to allow the IPG 10 to reportstatus information back to the external charger 50, such as by usingLoad Shift Keying as is well-known. For example, once circuitry in theIPG 10 detects that the battery 14 is fully charged, it can causecharging coil 30 to signal that fact back to the external charger 50 sothat charging can cease. Like the external controller 40, externalcharger 50 generally comprises a hand-holdable and portable housing.

External controller 40 and external charger 50 are described in furtherdetail in U.S. Patent Application Publication 2015/0080982. Note alsothat the external controller 40 and external charger 50 can be partiallyor fully integrated into a single external system, such as disclosed inU.S. Pat. Nos. 8,335,569 and 8,498,716.

SUMMARY

A method for assessing the suitability of a candidate patient forneurostimulation therapy is disclosed, which may comprise: presentingfrom a computer device one or more virtual environments to the candidatepatient; receiving at the computer device one or more physiologicalmeasurements taken from the candidate patient in response to each one ofthe one or more virtual environments; and determining at the computerdevice a composite response score based on the one or more physiologicalmeasurements; wherein the composite response score is useful fordetermining whether the candidate patient is a suitable candidate forneurostimulation therapy.

Determining the composite response score may comprise determining avirtual environment response score for each virtual environment usingthe one or more physiological measurements taken from the candidatepatient in response to that virtual environment, and using the virtualenvironment response scores to determine the composite response score.

The virtual environment may be presented to the candidate patient usinga headset or using a virtual reality room.

The method may further comprise determining at the computer devicewhether the candidate patient is a suitable candidate forneurostimulation therapy based on the composite response score.Determining at the computer device whether the candidate patient is asuitable candidate for neurostimulation therapy may comprise comparingthe composite response score to a threshold.

The one or more physiological measurements may be taken from thecandidate patient using one or more physiological sensors associatedwith the patient. The one or more physiological sensors may comprise oneor more of a heart sensor, a blood pressure sensor, a galvanic skinresponse sensor, a respiration rate sensor, an electrocardiogram sensor,a chemical sensor, a neurological sensor, an eye sensor, a temperaturesensor, or a motion sensor.

At least one of the one or more virtual environments may comprise animage of a person performing an activity. At least one of the one ormore virtual environments may also comprise an image of aneurostimulator implant procedure. At least one of the one or morevirtual environments may still further comprise an image indicative ofpain in a person. At least one of the one or more virtual environmentsfurther may also comprise an image of neurostimulation therapy beingapplied to the person and a decrease of the pain in the image indicativeof pain in the person. At least one of the one or more virtualenvironments may also comprises an image relevant to a physiologicalcondition of the candidate patient. At least one of the one or morevirtual environments may comprise an image designed to elicit a movementresponse from the candidate patient.

The neurostimulation therapy may comprise spinal cord stimulationtherapy. The computing device may comprise a clinician programmerconfigured to communicate with a neurostimulator device.

A non-transitory computer readable media including instructionexecutable on a computer device is disclosed, wherein the instructionswhen executed may be configured to assess the suitability of a candidatepatient for neurostimulation therapy by: presenting from the computerdevice one or more virtual environments to the candidate patient;receiving at the computer device one or more physiological measurementstaken from the candidate patient in response to each one of the one ormore virtual environments; and determining at the computer device acomposite response score based on the one or more physiologicalmeasurements; wherein the composite response score is useful fordetermining whether the candidate patient is a suitable candidate forneurostimulation therapy. The non-transitory computer readable media mayalso include instructions consistent with the method described earlier.

A method for assessing a patient having a neurostimulator is disclosed,which may comprise: communicating from a computer device a plurality ofsets of stimulation parameters for execution by the patient'sneurostimulator, wherein each of the sets of stimulation parameters iscommunicated to the patient's neurostimulator at a different time;presenting from the computer device one or more virtual environments tothe patient during the execution of each of the sets of stimulationparameters; receiving at the computer device one or more physiologicalmeasurements taken from the patient during the execution of each of thesets of stimulation parameters; determining at the computer device atherapeutic efficacy score for each of the sets of stimulationparameters based on the one or more physiological measurements takenfrom the patient during that set of stimulation parameters; anddetermining at the computer device a set of stimulation parameters forthe patient using the therapeutic efficacy scores.

The one or more virtual environments may be presented to the patientduring execution of one of the sets of stimulation parameters is basedon that set of stimulation parameters. The one or more virtualenvironments may be presented to the patient during execution of one ofthe sets of stimulation parameters is based the one or morephysiological measurements received during that set of stimulationparameters. The one or more virtual environments may be presented to thepatient during execution of one of the sets of stimulation parameters isbased on that set of stimulation parameters and is based on the one ormore physiological measurements received during that set of stimulationparameters. The one or more virtual environments presented to thepatient during execution of one of the sets of stimulation parametersmay comprise an image indicative of pain derived from the one or morephysiological measurements received during that set of stimulationparameters.

The virtual environment may be presented to the patient using a headset.The virtual environment may be presented to the using a virtual realityroom.

Determining the set of stimulation parameters using the therapeuticefficacy scores may comprise determining the set of stimulationparameters having a best of the therapeutic efficacy scores.

The one or more physiological measurements may be taken from the patientusing one or more physiological sensors associated with the patient. Theone or more physiological sensors may comprise one or more of a heartsensor, a blood pressure sensor, a galvanic skin response sensor, arespiration rate sensor, an electrocardiogram sensor, a chemical sensor,a neurological sensor, an eye sensor, a temperature sensor, or a motionsensor.

At least one of the one or more virtual environments may comprise animage of a person performing an activity. At least one of the one ormore virtual environments may comprise an image designed to elicit amovement response from the candidate patient.

The neurostimulation therapy may comprise spinal cord stimulationtherapy. The computing device may comprise a clinician programmerconfigured to communicate with the patient's neurostimulator.

A non-transitory computer readable media including instructionexecutable on a computer device is disclosed, wherein the instructionswhen executed may be configured to assess a patient having aneurostimulator by: communicating from the computer device a pluralityof sets of stimulation parameters for execution by the patient'sneurostimulator, wherein each of the sets of stimulation parameters iscommunicated to the patient's neurostimulator at a different time;presenting from the computer device one or more virtual environments tothe patient during the execution of each of the sets of stimulationparameters; receiving at the computer device one or more physiologicalmeasurements taken from the patient during the execution of each of thesets of stimulation parameters; determining at the computer device atherapeutic efficacy score for each of the sets of stimulationparameters based on the one or more physiological measurements takenfrom the patient during that set of stimulation parameters; anddetermining at the computer device a set of stimulation parameters forthe patient using the therapeutic efficacy scores. The non-transitorycomputer readable media may also include instructions consistent withthe method described earlier.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an implantable pulse generator (IPG) and different types ofleads that are connectable to the IPG in accordance with an example ofthe disclosure.

FIG. 2 shows a cross section of the IPG of FIG. 1 as implanted in apatient, as well as external devices that support the IPG, including anexternal charger and external controller in accordance with an exampleof the disclosure.

FIG. 3 shows components of a clinician's programmer system, includingcomponents for communicating with an external trial stimulator inaccordance with an example of the disclosure.

FIG. 4 shows an example of a virtual or augmented reality system inaccordance with an example of the disclosure.

FIG. 5 is a flow chart that shows various aspects of a patient selectionprocess that utilizes a virtual or augmented reality system inaccordance with an example of the disclosure.

FIG. 6 is a flow chart that shows various aspects of a stimulationevaluation process that utilizes a virtual or augmented reality systemin accordance with an example of the disclosure.

FIG. 7 illustrates a representative computing environment on whichsoftware that provides a patient selection process and/or a stimulationevaluation process using a virtual or augmented reality system may beexecuted in accordance with an aspect of the disclosure.

DETAILED DESCRIPTION

As mentioned above, the electrical stimulation that the IPG 10 iscapable of delivering is highly customizable with respect to selectedelectrodes, electrode current amplitude and polarity, pulse duration,pulse frequency, etc. Due to uncertainties in the location of electrodeswith respect to neural targets, the physiological response of a patientto stimulation patterns, and the nature of the electrical environmentwithin which the electrodes are positioned, it is difficult to determinethe stimulation settings that might provide effective stimulationtherapy without employing a trial and error approach. Thus, to determinewhether the IPG 10 is capable of delivering effective therapy, and, ifso, the stimulation settings that define such effective therapy, thepatient's response to different stimulation settings is typicallyevaluated during a trial stimulation phase prior to the permanentimplantation of the IPG 10.

During the trial stimulation phase, the distal ends of the lead(s) areimplanted within the epidural space along the spinal cord while theproximal ends of the lead(s), including the electrode terminals 20, areultimately coupled to an external neurostimulator such as external trialstimulator (ETS) 70, which is not implanted in the patient. The ETS 70essentially mimics operation of the IPG 10 to provide stimulation to theimplanted electrodes 16. This allows the effectiveness of stimulationtherapy to be verified for the patient, such as whether therapy hasalleviated the patient's symptoms (e.g., pain). Trial stimulation usingthe ETS 70 further allows for the determination of particularstimulation settings that seem promising for the patient to use once theIPG 10 is later implanted into the patient.

Referring to FIG. 3, the stimulation settings that are executed by theETS 70 can be provided or adjusted via a wired or wireless link(wireless link 92 shown) from an additional external device known as aclinician's programmer 200, which includes features that enable aclinician to hone in on the appropriate stimulation therapy settings. Asshown, CP system 200 can comprise a computing device 202, such as adesktop, laptop, or notebook computer, a tablet, a mobile smart phone, aPersonal Data Assistant (PDA)-type mobile computing device, etc.(hereinafter “CP computer”). In FIG. 3, CP computer 202 is shown as alaptop computer that includes typical computer user interface means suchas a screen 204, a mouse, a keyboard, speakers, a stylus, a printer,etc., not all of which are shown for convenience. Also shown in FIG. 3is a communication head 210, which is coupleable to a suitable port onthe CP computer 202, such as a USB port 206, for example. While the CPsystem is shown in communication with the ETS 70, the CP system 200 isalso configured to communicate with the IPG 10 once it is implanted.

Communication between the CP system 200 and the ETS 70 or IPG 10 maycomprise magnetic inductive or short-range RF telemetry schemes asalready described, and in this regard the ETS 70 and the CP computer 202and/or the communication head 210 (which can be placed proximate to theIPG 10 or ETS 70) may include antennas compliant with the telemetrymeans chosen. For example, the communication head 210 can include a coilantenna 212 a, a short-range RF antenna 212 b, or both. The CP computer202 may also communicate directly with the IPG 10 or the ETS 70, forexample using an integral short-range RF antenna 212 b.

If the CP system 200 includes a short-range RF antenna (either in CPcomputer 202 or communication head 210), such antenna can also be usedto establish communication between the CP system 200 and other devices,and ultimately to larger communication networks such as the Internet.The CP system 200 can typically also communicate with such othernetworks via a wired link provided at an Ethernet or network port 208 onthe CP computer 202, or with other devices or networks using other wiredconnections (e.g., at USB ports 206).

To program stimulation parameters, the clinician interfaces with aclinician's programmer graphical user interface (CP GUI) 94 provided onthe display 204 of the CP computer 202. As one skilled in the artunderstands, the CP GUI 94 can be rendered by execution of CP software96 on the CP computer 202, which software may be stored in the CPcomputer's non-volatile memory 220. Such non-volatile memory 220 mayinclude one or more non-transitory computer-readable storage mediumsincluding, for example, magnetic disks (fixed, floppy, and removable)and tape, optical media such as CD-ROMs and digital video disks (DVDs),and semiconductor memory devices such as Electrically ProgrammableRead-Only Memory (EPROM), Electrically Erasable Programmable Read-OnlyMemory (EEPROM), and USB or thumb drive. One skilled in the art willadditionally recognize that execution of the CP software 96 in the CPcomputer 202 can be facilitated by control circuitry 222 such as amicroprocessor, microcomputer, an FPGA, other digital logic structures,etc., which is capable of executing programs in a computing device. Suchcontrol circuitry 222 when executing the CP software 96 will in additionto rendering the CP GUI 94 enable communications with the ETS 70 througha suitable antenna 212 a or 212 b, either in the communication head 210or the CP computer 202 as explained earlier, so that the clinician canuse the CP GUI 94 to communicate the stimulation parameters to the ETS70.

Prior to the trial stimulation phase, patients are typically evaluatedto determine whether they are good candidates for SCS therapy. Such anevaluation may include both physical and psychological aspects. Theinventors have observed, however, that despite patient screening, arelatively high proportion of patients do not go forward with fullimplantation after the trial phase or ultimately terminate therapy afterfull implantation of the IPG 10. The inventors have further observedthat one drawback of existing candidate screening is the subjectivity ofthe evaluations. Different practitioners may assign different weights tovarious patient factors and candidate patients, often driven by a desireto be approved for SCS therapy, may exaggerate or understate differentfactors in hopes of being assessed as a suitable candidate. Thus, thereexists a need to improve patient screening to more successfully identifypatients that are suitable candidates for SCS therapy.

Disclosed herein is a virtual or augmented reality system that in afirst aspect removes some of the subjectivity of patient evaluations forSCS or other neurostimulation therapies. As described below, the systemmay present a virtual environment to a prospective or current SCSpatient that is a wholly simulated environment, or the system maypresent an augmented environment to the patient that supplements anormal environment that the patient otherwise experiences. Forsimplicity and for the purpose of this disclosure and the claims, a“virtual” environment, system, reality, or equipment, etc. refersrespectively to both virtual and augmented environments, systems,realities, or equipments, etc.

As illustrated in FIG. 4, the virtual reality system may include avirtual reality headset 420. As is known, a virtual reality headset 420fits snugly against the user's face such that the user's only visualperception is that of the virtual reality that is presented via adisplay inside the headset 420. The headset 420 is connected to animproved CP system 200′ via a wired or wireless connection (e.g., viamagnetic inductive or short-range RF telemetry schemes as alreadydescribed). In one embodiment, the improved CP system 200′ may includethe same functionality and hardware as the CP system 200 describedabove, but the improved CP system 200′ may execute improved CP software96′ to provide various features as described below. While an enclosedheadset 420 is shown, the CP system 200′ may alternatively be connectedto an open headset that enables the user to view their surroundings butthat also presents an image via a display to create an augmentedreality. One type of such headset is described in U.S. PatentPublication 2015/0360038, which is incorporated herein by reference inits entirety. In yet another embodiment, the CP system 200′ may beconnected to a large and perhaps curved display that is positioned in avirtual reality room, or to a projector that provides an image to a(curved) wall in a virtual reality room. In such an embodiment, thepatient may not wear a headset but may be positioned in the room suchthat they are immersed in the virtual reality that is presented via thedisplay. Virtual reality images presented to the user by the system cancomprise static images, scenes, animations, video, and the like.

Also connected to the improved CP system 200′ are a number of patientsensors, again connected via a wired or wireless connection. The sensorscan include one or more of a heart sensor 402, a blood pressure sensor404, a galvanic skin response (GSR) sensor 406, a respiration ratesensor 408, an electrocardiogram (ECG) sensor 410, a chemical sensor412, a neurological sensor 414, an eye sensor (e.g., camera) 416 fortracking eye movement and/or pupil diameter, a temperature sensor 417,and a motion sensor 418 to monitor movements of the patient's head orother body parts. One or more of the sensors may take the form of awrist watch that can be worn by the patient, a cuff that is placedaround the patient's arm, or other known forms. Other physiologicalsensors can be used as part of the disclosed system and the sensorsillustrated in FIG. 4 are merely examples.

The heart sensor 402 can comprise a heart rate sensor, such as aperipheral pulse sensor. In one example, the heart sensors 402 candetect various activities of the heart, and may provide other data aswell. For example, the heart sensor 402 may comprise a pulse oximeterable to describe gas content of the patient's blood. The ECG sensor 410may comprise multiple leads that are placed at different positions onthe patient's body as is known. Such leads may be wired to an ECGmonitor (i.e., the ECG sensor 410) that is connected to the CP system200′. The chemical sensor 412 may comprise a sensor that measures thelevels of certain chemicals in the patient's blood or other bodilyfluid. For example, the chemical sensor may measure levels of cortisol,which is indicative of the level of stress the patient is experiencing,in the patient's blood. Blood samples may be taken periodically whilethe patient experiences a virtual reality, and the results may becommunicated from the chemical sensor 412 to the CP system 200′. Theneurological sensor 414 may include one or more of different types ofneurological sensors such as an electroencephalography (EEG) sensor, anelectrooculography sensor, and a functional near-infrared spectroscopy(fNIRS) sensor. As is known, each of these types of neurological sensorsmay include multiple skin-mounted devices (e.g., electrodes) that arewired to the respective sensor 414. In one embodiment, some or all ofthe skin-mounted devices may be positioned inside the headset 420 suchthat they are in contact with the patient's skin when the headset 420 isworn. The devices may report measurements back to the respectiveneurological sensor 414, which may communicate neurological parametersto the CP system 200′ while the patient experiences a virtual realityenvironment. The eye sensor 416 may include one or more cameras and maysimilarly be mounted on the inside of the headset 420 such that itdetects the patient's eyes while the patient experiences the virtualreality environment. Temperature sensor 417 may comprise a sensor tomeasure a core or peripheral temperature of the patient. The motionsensor 418 for tracking the patient's movements may comprise one or moreaccelerometers or gyroscopes one or more of which may similarly bemounted to the headset 420 or worn by the patient.

FIG. 5 illustrates a patient evaluation process 500 precedingimplantation that utilizes the virtual reality environment to assesswhether a patient is a good candidate to receive SCS therapy. The useris first fit with the virtual reality equipment and one or more patientsensors (502). As described above, the virtual reality equipment mayinclude a VR headset 420, a different type of headset, or a virtualreality room. The patient sensors may include one or more of the patientsensors described above with respect to FIG. 4.

At this point it is optionally useful to measure physiological responsesfrom the sensors and provide such measurements to the CP system 200′(503). This can be useful first to ensure that the sensors are workingcorrectly, and second to establish baseline measurements from thesensors before the patient is exposed to the virtual environment(s) tofollow.

After the patient has been fit with the patient sensors and the virtualreality equipment, they are presented one or more virtual environments(504). The virtual environment may be presented via a display that isdriven by the CP system 200′ (e.g., the headset display or in thevirtual reality room).

In one embodiment, the virtual environment may comprise an image that isdesigned to elicit a response in the patient. For example, the virtualenvironment may depict a person performing an activity that may causepain such as lifting a heavy object, climbing stairs, rising from aseated position, etc. The virtual environment may alternatively depict aperson performing an activity that is not likely to cause pain such aslying in bed or sitting down. The virtual environment may also depict anSCS implant procedure with the leads and IPG being implanted in anactual or virtual patient. The virtual environment may also present adepiction of pain. For example, the virtual environment may depict animage of pain in a person. In one embodiment, the image of pain may bepositioned in a location relative to an image of a person thatcorresponds to the location at which the patient experiences pain (e.g.,the image may appear at the depicted person's lower back if the patientexperiences lower back pain). The virtual environment may further depictan image of SCS therapy being applied and, in conjunction, an image thatshows the indication of pain decreasing in size. The virtual environmentmay also depict different types of environments such as a depiction of aperson interacting with people, a depiction of the person beingdependent upon a caregiver, a depiction of a person being independent asa result of SCS therapy, or a depiction of a person experiencing a typeof psychologically stressful event. These types of virtual environmentsmay be designed to evaluate the patient's psychological condition.

Other types of virtual environments may be designed to evaluate thepatient's physical condition and elicit a movement response from thepatient. These types of environments may prompt the patient to takecertain actions. For example, a virtual environment may depict objectsmoving toward the patient and may prompt the patient to attempt to dodgethe objects. Another type of virtual environment may prompt the patientto mimic an activity that is being performed by the person that isdepicted in the virtual environment. For example, the virtualenvironment may prompt the user to mimic a depiction of a person that isstanding up, balancing on one leg, kneeling down, bending over at thewaist, etc.

In one embodiment, images that are presented in the virtual environmentmay be actual images of the patient. In another embodiment, the imagesmay be an avatar that is generated to look like the patient. In yetanother embodiment, the image may be of a random person or avatar andnot related to the particular patient. The particular image that isdepicted in the virtual environment may be specifically chosen for theparticular patient and may be relevant to a physiological condition ofthe patient. For example, if the patient experiences pain when risingfrom a seated position, an image that depicts that activity may bechosen for the patient. In this regard, the CP system 200′ may enable apractitioner to control the virtual environment that is being presented.For example, the CP software 96′ may provide an interface that enablesthe practitioner to select an image that is presented as the virtualenvironment, to determine how long the particular virtual environment ispresented, etc.

While the virtual environment is being presented to the patient, thepatient's physiological responses to the virtual environment aremeasured by the one or more patient sensors (the term physiologicalresponses is used here to describe responses received from any of thepatient sensors). The physiological responses measured by the sensorsare received at the CP system 200′ (506). These responses can provide anindication of the patient's anxiety, stress, and pain, for example. Theresponses can also provide an indication of the patient's physicalabilities in response to virtual environments that test such physicalabilities (e.g., via motion sensors 418).

Based on the received physiological responses from the sensors, aresponse score is calculated at the CP system 200′ for the virtualenvironment (508). In one embodiment, the response score may becalculated in accordance with a change in each of one or morephysiological parameters from a baseline level (503) to the recordedlevel during the presentation of the virtual environment. For example,if the patient's heart rate increases from 80 beats per minute to 120beats per minute in response to presentation of the virtual environment,the response score (at least the portion that is attributable to theheart sensor 402) may be calculated on the basis of the 40 beat perminute increase in the patient's heart rate in response to the virtualenvironment. As will be understood, the physiological responses that arereceived at the CP system 200′ may be weighted differently. For example,the EEG measurements may be considered to provide a more valuablemeasure of the patient's response to a virtual environment and so it maybe accorded more weight in the calculation of the response score.

After the response score is calculated, it is determined if the virtualenvironment is the last (or only) one to be presented to the patient(510). If not, a next virtual environment is presented to the patient(504) and the process is repeated. While the response score calculation(508) and next virtual environment presentation (504) are shown as beingperformed sequentially, this is not specifically necessary. Calculationof the response score for a particular virtual environment can occurduring the presentation of a subsequent virtual environment.

If the virtual environment that was presented to the patient is the lastvirtual environment to be presented, a composite response score iscalculated (512). The composite response score is calculated from theresponse scores associated with each of the virtual environments. In oneembodiment, the composite response score may be a sum of the responsescores associated with each of the virtual environments that werepresented to the patient. In another embodiment, the composite responsescore is an average of the response scores associated with each of thevirtual environments that were presented to the patient. In anotherembodiment, one or more of the highest and lowest response scoresassociated with the virtual environments that were presented to thepatient may be eliminated and thus not included in the calculation ofthe composite response score. In yet another embodiment, certain virtualenvironments may be deemed more relevant and their associated responsescores may be given more weight than response scores associated withother virtual environments.

After the composite response score is calculated, it is compared to athreshold score (514). If the calculated composite response scoreexceeds the threshold, the patient is determined to be a good candidatefor SCS therapy (516) and may be progressed to the next round ofevaluation (e.g., trial stimulation). If the calculated compositeresponse score is less than the threshold, the patient is determined notto be a good candidate for SCS therapy (518).

As can be understood, the process 500 provides an objective evaluationof a candidate patient's suitability for receiving SCS therapy. Becausethe process 500 relies upon objective measurements of the candidatepatient's response to one or more virtual environments, the subjectivityof current patient evaluation processes is removed and a more accurateassessment of the candidate patient's suitability for therapy can bedetermined. However, process 500 can also be performed after the patienthas been implanted and is receiving SCS therapy. For example, theprocess 500 may be performed prior to a trial stimulation phase, duringa trial stimulation phase, and after permanent implantation of the IPG10. In such an embodiment, the patient's responses to the virtualenvironments may be compared to those in a prior evaluation (e.g., priorto a trial stimulation phase) to evaluate the effectiveness of thestimulation therapy that is being provided.

FIG. 6 illustrates a stimulation evaluation process 600 that utilizesthe virtual reality environment for a patient that has already beenimplanted, and thus is capable of receiving stimulation delivered via aneurostimulator (i.e., via an ETS 70 during a trial stimulation phase orvia an IPG 10 after its permanent implantation). Stimulation evaluationprocess 600 is useful to choosing optimal stimulation settings for thepatient.

Just as with the patient evaluation process 500, the patient is firstfit with the virtual reality equipment and the patient sensors (602). Atthis point it can be useful to receive measurements from the sensors(603) to ensure that they are functioning properly and as a baseline.

Stimulation settings can then be communicated to the patient'sneurostimulator via improved CP system 200′. As noted above, thestimulation settings can include various stimulation parameters such asthe selected electrodes, electrode current amplitude and polarity, pulseduration, pulse frequency, etc. In one embodiment, the stimulationsettings may be manually selected by a practitioner (e.g., via the CPsystem 200′) for the specific patient. In another embodiment, thestimulation parameters may be selected from a group of pre-configuredstimulation settings and the process 600 may cycle through differentones of the stimulation settings in the group.

One or more virtual environments are then presented to the patient, andphysiological data is received from the sensors at the CP system 200′(606). Just as with the process 500, the virtual environment may bepresented via a display that is driven by the CP system 200′ (e.g., theheadset display or in the virtual reality room).

In one embodiment, the virtual environment is based on the stimulationsettings and/or the physiological data. For example, the stimulationsettings may be utilized to generate an image of the stimulation that isbeing provided and the physiological data may be utilized to generate animage of the level of pain that the patient is experiencing. The levelof pain that the patient is experiencing may be calculated according toall or a subset of the physiological data from the patient sensors. Inone embodiment, these images of pain and stimulation may be presented onan avatar or another image of a person, and the images may be adjustedas the stimulation settings and the physiological data change. In oneembodiment, the image of pain may reduce in size whenever stimulation isbeing provided regardless of the physiological data. Such an embodimentmay enable the patient to visualize the effectiveness of the stimulationtherapy that is being provided even when the physiological data may notyet reflect a change in the level of pain. The virtual environment mayprompt the patient to focus intently on the images of stimulation andpain, and the pain image may be reduced in size as the patient focuses.This again enables the patient to visualize the effectiveness of thestimulation therapy that is being provided.

In one embodiment, the virtual environment may depict an image of aperson performing activities such as walking in place, bending from sideto side, or squatting down. In such an embodiment, the virtualenvironment may prompt the patient to mimic the activities that arebeing performed by the person that is depicted in the virtualenvironment. The virtual environment may utilize motion sensor data topresent an image of the patient's movements as the patient attempts tomimic the activities that are being performed by the person that isdepicted in the virtual environment. In one embodiment, the image of thepatient's movements may be exaggerated when stimulation is beingprovided to enable the patient to visualize the effectiveness of thestimulation therapy. The virtual environment(s) presented by thestimulation evaluation process 600 may also comprise the virtualenvironments presented by the patient evaluation process 500 discussedabove.

The presentation of the virtual environment (which may comprise multipledifferent types of images for each set of stimulation settings)continues for a length of time that enables the collection of asufficient quantity of physiological data to evaluate the effectivenessof the stimulation settings. The length of time that is required toobtain such a quantity of physiological data may be a user-selectableparameter of the process 600.

For each set of stimulation settings, after a sufficient amount of datahas been received from the patient sensors, a therapeutic efficacy scoreis calculated (610). The therapeutic efficacy score may be based on apain score that is calculated from the physiological data that isreceived. More specifically, the therapeutic efficacy score may bedetermined from a difference between a baseline pain score that iscalculated from physiological data that is received when no stimulationis provided (603) and the pain score that is calculated fromphysiological data that is received when stimulation using theparticular stimulation settings is provided. If the current stimulationsettings are not the last settings to be evaluated, new stimulationsettings are selected (614) and communicated to the patient'sneurostimulator (604) and the process continues. If the currentstimulation settings are the last settings to be evaluated, the optimalstimulation settings are identified (616). In one embodiment, theoptimal stimulation settings are the stimulation settings that areassociated with the highest therapeutic efficacy score. After theoptimal stimulation settings are determined, they may be communicated tothe patient's neurostimulator.

As can be understood, the process 600 provides a patient with avisualization of the effectiveness of stimulation therapy and providesan objective measurement of the effectiveness of various stimulationsettings. Because the process 600 relies upon objective measurements ofthe patient's response to different stimulation settings, a moreaccurate assessment of the effectiveness of different stimulationsettings can be determined, and optimal stimulation settings can bedetermined. In one embodiment, the process 600 may be performed one ormore times during a trial stimulation phase or after permanentimplantation of the IPG 10. In such an embodiment, the patient'sresponses to different stimulation settings can be periodicallyevaluated to ensure that the most optimal stimulation therapy is beingprovided.

FIG. 7 illustrates the various components of an example CP computer 202that may be configured to execute CP software 96′, which CP software 96′may include program code that, when executed, provides the functionalityof processes 500 and/or 600. The CP computer 202 can include theprocessor 222, memory 224, storage 220, graphics hardware 226,communication interface 230, user interface adapter 232 and displayadapter 234—all of which may be coupled via system bus or backplane 236.Memory 224 may include one or more different types of media (typicallysolid-state) used by the processor 222 and graphics hardware 226. Forexample, memory 224 may include memory cache, read-only memory (ROM),and/or random access memory (RAM). Storage 220 may comprise anon-transitory computer readable medium for storing computer programinstructions or software (e.g., CP software 96′), including instructionsfor implementing processes 500 and 600, preference information, deviceprofile information, and any other suitable data. Storage 220 mayinclude one or more non-transitory computer-readable storage mediumsincluding, for example, magnetic disks (fixed, floppy, and removable)and tape, optical media such as CD-ROMs and digital video disks (DVDs),and semiconductor memory devices such as Electrically ProgrammableRead-Only Memory (EPROM), Electrically Erasable Programmable Read-OnlyMemory (EEPROM), and USB or thumb drive. Memory 224 and storage 220 maybe used to tangibly retain computer program instructions or codeorganized into one or more modules and written in any desired computerprogramming language. As will be understood, the CP software 96′ may bestored on a medium such as a CD or a USB drive, pre-loaded on acomputing device such as the CP computer 202, or made available fordownload from a program repository via a network connection.Communication interface 230 (which may comprise, for example, the ports206 or 208) may be used to connect the CP computer 202 to a network.Communications directed to the CP computer 202 may be passed through aprotective firewall 238. Such communications may be interpreted via webinterface 240 or voice communications interface 242. Illustrativenetworks include, but are not limited to: a local network such as a USBnetwork; a business' local area network; or a wide area network such asthe Internet. User interface adapter 232 may be used to connect akeyboard 244, microphone 246, pointer device 248, speaker 250 and otheruser interface devices such as a touch-pad and/or a touch screen (notshown). Display adapter 234 may be used to connect display 204 andprinter 252. Processor 222 may include any programmable control device.Processor 222 may also be implemented as a custom designed circuit thatmay be embodied in hardware devices such as application specificintegrated circuits (ASICs) and field programmable gate arrays (FPGAs).The CP computer 202 may have resident thereon any desired operatingsystem.

While the above processes 500 and 600 have been described in terms ofits performance on a CP computer 202, it will be understood that theprocesses can also be performed on a different type of device such as apersonal electronics device like a phone or tablet, or an externaldevice capable of communicating with an IPG or ETS. Moreover, while theprocesses 500 and 600 have been described as being implemented as partof CP software 96′, it will be understood that the processes 500 and 600may alternatively be embodied in software that is separate and distinctfrom the CP software 96. Finally, it should be understood that the stepsof processes 500 and 600 can occur in different orders, and that not allillustrated steps are necessary in a useful implementation. Further,additional steps can be added.

While the invention herein disclosed has been described by means ofspecific embodiments and applications thereof, numerous modificationsand variations could be made thereto by those skilled in the art withoutdeparting from the scope of the invention set forth in the claims.

What is claimed is:
 1. A method for assessing the suitability of acandidate patient for neurostimulation therapy, comprising: presentingfrom a computer device one or more virtual environments to the candidatepatient; receiving at the computer device one or more physiologicalmeasurements taken from the candidate patient in response to each one ofthe one or more virtual environments; and determining at the computerdevice a composite response score based on the one or more physiologicalmeasurements; wherein the composite response score is useful fordetermining whether the candidate patient is a suitable candidate forneurostimulation therapy.
 2. The method of claim 1, wherein determiningthe composite response score comprises determining a virtual environmentresponse score for each virtual environment using the one or morephysiological measurements taken from the candidate patient in responseto that virtual environment, and using the virtual environment responsescores to determine the composite response score.
 3. The method of claim1, wherein the virtual environment is presented to the candidate patientusing a headset.
 4. The method of claim 1, wherein the virtualenvironment is presented to the candidate patient using a virtualreality room.
 5. The method of claim 1, further comprising determiningat the computer device whether the candidate patient is a suitablecandidate for neurostimulation therapy based on the composite responsescore.
 6. The method of claim 5, wherein determining at the computerdevice whether the candidate patient is a suitable candidate forneurostimulation therapy comprises comparing the composite responsescore to a threshold.
 7. The method of claim 1, wherein the one or morephysiological measurements are taken from the candidate patient usingone or more physiological sensors associated with the patient.
 8. Themethod of claim 7, wherein the one or more physiological sensorscomprise one or more of a heart sensor, a blood pressure sensor, agalvanic skin response sensor, a respiration rate sensor, anelectrocardiogram sensor, a chemical sensor, a neurological sensor, aneye sensor, a temperature sensor, or a motion sensor.
 9. The method ofclaim 1, wherein at least one of the one or more virtual environmentscomprises an image of a person performing an activity.
 10. The method ofclaim 1, wherein at least one of the one or more virtual environmentscomprises an image of a neurostimulator implant procedure.
 11. Themethod of claim 1, wherein at least one of the one or more virtualenvironments comprises an image indicative of pain in a person.
 12. Themethod of claim 11, wherein at least one of the one or more virtualenvironments further comprises an image of neurostimulation therapybeing applied to the person and a decrease of the pain in the imageindicative of pain in the person.
 13. The method of claim 1, wherein atleast one of the one or more virtual environments comprises an imagerelevant to a physiological condition of the candidate patient.
 14. Themethod of claim 1, wherein at least one of the one or more virtualenvironments comprises an image designed to elicit a movement responsefrom the candidate patient.
 15. The method of claim 1, wherein theneurostimulation therapy comprises spinal cord stimulation therapy. 16.The method of claim 1, wherein the computing device comprises aclinician programmer configured to communicate with a neurostimulatordevice.
 17. A non-transitory computer readable media includinginstruction executable on a computer device, wherein the instructionswhen executed are configured to assess the suitability of a candidatepatient for neurostimulation therapy by: presenting from the computerdevice one or more virtual environments to the candidate patient;receiving at the computer device one or more physiological measurementstaken from the candidate patient in response to each one of the one ormore virtual environments; and determining at the computer device acomposite response score based on the one or more physiologicalmeasurements; wherein the composite response score is useful fordetermining whether the candidate patient is a suitable candidate forneurostimulation therapy.